KDW

here is the story i bought a 455 (used) with the following:
1.6 roller rocker
comp cam springs
arp rocker studs
30 over speed pro l2323F
msd ign
performer intake
edelbrock 800
edelbrock heads
cam lunati 60803
th400
2500 stall
308 posi

its all in a 72 cutlass supreme

motor runs ok i need to wake it up was thinks the cam may not be a good match, the should be 9 to 10 compression. did a warm comp test car still had 155 to 157....

was told they is guy here that can help?

cutlassefi

That should run half decent, was the cam degreed?
Your gear is hurting you as well.

olds 307 and 403

Check where your cam is for degree, many timing sets are not accurate. Also make sure that POS Edelbrock carb is tuned properly. What are you running for timing? What distributor? With that cranking compression, you can get aggresive, like mid 50 degrees part throttle. Run maybe an extra degree or two over the stock base setting. You are probably around 9.6 to 1 with those pistons and your cranking compression is a touch low. How fresh is this motor? Maybe pull the heads and mill them a bit or go with better pistons with a smaller dish. A 3.23 gear would help a bit a well on the launch as Mark said.

Lee_A

That cam matches well with your gears and stall. Should easily run 12's and smoke the p!ss out of your tires - IF it is properly tuned. I agree with 307/403, the carb is probably FAR from properly tuned, and is likely holding you back more than anything. Borrow a 750 Holley from somebody and give it a test, I bet you'll be shocked.

cutlassefi

Wondering what would make you think that will automatically be "tuned" for his combo anymore than what he has. Curious.

Lee_A

I did make the assumption that KDW has common sense, and would borrow a carb from a reasonably similar motor, which was already running decently.


I've also pulled generic 750's off of a shelf, used them to test against Edelbrock carbs, and seen owners happy with the difference.


Here is a dyno graph of a guy with an Edelbrock on a 400 Pontiac. His dad had a 750 Demon (old) sitting around, and we threw it on and retested. I DID tweak the idle mixture screws, and changed the jets a few numbers.

KDW

Ok guy lmao ! Just looking for honest answer, is there anyway to find out where the cam is and time it from there?
If I bring it up to TDC and the balancer lines up is it safe to say I'm in the ball park?

Edelbrock( carter sty) my not be the perfect carb, I also have a freshly Rebuilt edelbock qj 1910 not sure of jetting, Holley 870 vs , QF 750

This post looks alover the board shouldn't we start with where the cam is and go from there?

Fun71

Since the balancer is bolted to the crank, and the pistons are bolted to the crank, it will tell you nothing at all about the relationship of the camshaft to the crankshaft/pistons. You could have no camshaft installed and the crank - balancer orientation would be the same. It will verify if the outer ring of the balancer has slipped, though.

KDW

thanks

olds 307 and 403

Any of those other carbs might be worth a try.